package code20210926;

public class C70 {

	public static void main(String[] args) {
		int n = 3;
		System.out.println(new C70().climbStairs(n));
	}
	public int climbStairs(int n) {
		int[] dp = new int[n+1];
		dp[0] = 1;
		dp[1] = 1;
		for(int i=2;i<dp.length;i++) {
			dp[i] = dp[i-1] + dp[i-2];
		}
		return dp[n];
    }
}
